System and method of balancing output currents of a plurality of power supply units for supplying power to a system load

Abstract

Embodiments of the present disclosure relates to a method and device for balancing a supply current. In one embodiment, a current supply current for a load is detected. A first signal representing the current supply current is transmitted to a digital logic module. A second signal representing a maximum supply current and a third signal representing a minimum supply current are received from the digital logic module. A subsequent supply current for the load is determined based on the current supply current, the maximum supply current and the minimum supply current. By using the method and device according to the embodiments of the present disclosure, the supply currents of a plurality of power supply units for the load can be balanced a simple way with a low hardware cost.

What is claimed is: 
     
       1. A method of balancing a supply current, comprising:
 transmitting, from a first power supply unit (PSU) to a digital logic circuit, a first output current signal representing a first output current of the first PSU for a system load; 
 receiving, from the digital logic circuit, an average output current signal representing an average output current, the average output current being an average of the first output current and at least one second output current of at least one second PSU for the system load; and 
 obtaining a subsequent output current of the first PSU for the system load based on the first output current and the average output current. 
 
     
     
       2. The method of  claim 1  wherein the obtaining of the subsequent output current includes obtaining a difference between the first output current and the average output current, and obtaining the subsequent output current based on the difference. 
     
     
       3. The method of  claim 2  wherein the obtaining of the subsequent output current includes, in response to the difference being less than a predetermined threshold, maintaining the first output current as the subsequent output current. 
     
     
       4. The method of  claim 2  wherein the obtaining of the subsequent output current includes, in response to the difference being greater than a predetermined threshold and the average output current being greater than the first output current, increasing the first output current by a predetermined current amount, and using the increased first output current as the subsequent output current. 
     
     
       5. The method of  claim 4  wherein the increasing of the first output current by the predetermined current amount includes increasing an output voltage for the system load by a predetermined voltage amount. 
     
     
       6. The method of  claim 2  wherein the obtaining of the subsequent output current includes, in response to the difference being greater than a predetermined threshold and the average output current being less than the first output current, decreasing the first output current by a predetermined current amount, and using the decreased first output current as the subsequent output current. 
     
     
       7. The method of  claim 6  wherein the decreasing of the first output current by the predetermined current amount includes decreasing an output voltage for the system load by a predetermined voltage amount. 
     
     
       8. A first device for supplying power, comprising:
 a power output circuit configured to output a first output current of the first device to a system load; 
 a current sensing circuit configured to sense the first output current of the first device; and 
 a microprocessor configured:
 to transmit a first output current signal representing the first output current of the first device to a digital logic circuit; 
 to receive, from the digital logic circuit, an average output current signal representing an average output current, the average output current being an average of the first output current of the first device and at least one second output current of at least one second device for supplying power to the system load; and 
 to obtain a subsequent output current of the first device for the system load based on the first output current and the average output current. 
 
 
     
     
       9. The device of  claim 8  wherein the microprocessor is further configured to obtain a difference between the first output current and the average output current, and to obtain the subsequent output current based on the difference. 
     
     
       10. The device of  claim 9  wherein the microprocessor is further configured, in response to the difference being less than a predetermined threshold, to maintain the first output current as the subsequent output current. 
     
     
       11. The device of  claim 9  wherein the microprocessor is further configured, in response to the difference being greater than a predetermined threshold and the average output current being greater than the first output current, to increase the first output current by a predetermined current amount, and to use the increased first output current as the subsequent output current. 
     
     
       12. The device of  claim 11  wherein the microprocessor is further configured to increase an output voltage for the system load by a predetermined voltage amount. 
     
     
       13. The device of  claim 9  wherein the microprocessor is further configured, in response to the difference being greater than a predetermined threshold and the average output current being less than the first output current, to decrease the first output current by a predetermined current amount, and to use the decreased first output current as the subsequent output current. 
     
     
       14. The device of  claim 13  wherein the microprocessor is further configured to decrease an output voltage for the system load by a predetermined voltage amount. 
     
     
       15. A power source, comprising:
 the first device and the at least one second device for supplying power according to  claim 8 ; and 
 the digital logic circuit configured:
 to receive the first output current of the first device and the at least one second output current of the at least one second device; 
 to determine the average output current based on the first output current and the at least one second output current; and 
 to transmit the average output current signal representing the average output current to the first device and the at least one second device. 
 
 
     
     
       16. A method of balancing a supply current, comprising:
 transmitting, from a first power supply unit (PSU) to a digital logic circuit, a first output current signal representing a first output current of the first PSU for a system load; 
 receiving, from the digital logic circuit, a median output current signal representing a median output current, the median output current being a median of the first output current and at least one second output current of at least one second PSU for the system load; and 
 obtaining a subsequent output current of the first PSU for the system load based on the first output current and the median output current. 
 
     
     
       17. The method of  claim 16  wherein the obtaining of the subsequent output current includes obtaining a difference between the first output current and the median output current, and obtaining the subsequent output current based on the difference. 
     
     
       18. The method of  claim 17  wherein the obtaining of the subsequent output current includes, in response to the difference being less than a predetermined threshold, maintaining the first output current as the subsequent output current. 
     
     
       19. The method of  claim 17  wherein the obtaining of the subsequent output current includes, in response to the difference being greater than a predetermined threshold and the median output current being greater than the first output current, increasing the first output current by a predetermined current amount, and using the increased first output current as the subsequent output current. 
     
     
       20. The method of  claim 17  wherein the obtaining of the subsequent output current includes, in response to the difference being greater than a predetermined threshold and the median output current being less than the first output current, decreasing the first output current by a predetermined current amount, and using the decreased first output current as the subsequent output current.